Zeolite membrane and methods of making and using same for water desalination

Abstract

A novel zeolite membrane is manufactured using zeolite seeds that are deposited on a support material. The seeds are then further grown in a secondary growth step to form a membrane with inter-grown particles. The pore size of the zeolite membrane is in a range between 3 angstrom and 8 angstrom, which allows water to flow through the membrane at a relatively high flux rate while excluding dissolved ions. The novel zeolite membrane is surprisingly efficient for desalinating sea water using reverse osmosis. The zeolite membrane is capable of high rates of water flux rate and high percentage of ion rejection.

1 . A method for making a zeolite membrane suitable for desalinating water using reverse osmosis comprising:
 providing a support material;   providing a plurality of zeolite seed particles for use in forming a zeolite layer on the support material that is suitable for use in desalinating water using reverse osmosis, the zeolite seed particles comprising a zeolite with a pore diameter in a range from about 3 angstroms to about 8 angstroms;   depositing the zeolite seed particles on the support material to form an intermediate supported zeolite in preparation for forming the zeolite layer; and   performing a secondary growth of the zeolite seed particles by combining the intermediate supported zeolite with a zeolite reaction mixture and growing the zeolite seed particles under conditions suitable for zeolite crystal growth so as to form the zeolite layer on the support material and thereby form a zeolite membrane comprised of the support material and the zeolite layer, the zeolite layer having a thickness in a range from about 1 micron to about 300 micron and a pore diameter in order for the zeolite membrane to have flux and ion rejection rates suitable for water desalination.   
     
     
         2 . A method as in  claim 1 , wherein the thickness of the zeolite layer is in a range from about 10 microns to about 200 microns. 
     
     
         3 . A method as in  claim 1 , wherein the support material is a glass frit, stainless-steel-net, a-Al 2 O 3 , a copper net, or a combination thereof 
     
     
         4 . A method as in  claim 1 , wherein the zeolite seed particles have a size in a range from about 20 nm to about 500 nm. 
     
     
         5 . A method as in  claim 1 , wherein the zeolite seed particles are provided in a seed particle suspension, wherein depositing the seed particles includes contacting the seed particle suspension with the support material. 
     
     
         6 . A method as in  claim 5 , wherein the concentration of the zeolite seed particles in the suspension is in a range from about 5 g/l to about 100 g/l. 
     
     
         7 . A method as in  claim 5 , wherein the zeolite seed particles are deposited on the support material in a concentration in a range from about 10 g/l to about 200 g/l. 
     
     
         8 . A method as in  claim 5 , wherein the support material is wetted before contacting the zeolite seed particle suspension with the support material, thereby limiting the absorption of the zeolite seed particles within the support. 
     
     
         9 . A method as in  claim 1 , wherein the zeolite reaction mixture comprises a ratio of silica to alumina in a range from about 10 to about 500. 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . A method as in  claim 1 , wherein the support material has a pore diameter in a range from about 1 micron to about 100 microns. 
     
     
         13 . A method as in  claim 1 , wherein the zeolite seed particles are selected from the group consisting of silicalite-1, ZSM-5, zeolite A, zeolite P, zeolite SPO 34 , and combinations thereof. 
     
     
         14 . A method as in  claim 1 , wherein the zeolite layer is comprised of inter-grown zeolite crystals having a diameter in a range from about 20 nm to about 500 nm. 
     
     
         15 . A method as in  claim 1 , wherein the zeolite seed particles comprise a zeolite with a pore diameter is in a range from about 4 angstroms to about 6 angstroms. 
     
     
         16 . (canceled) 
     
     
         17 . A method as in  claim 1 , wherein the zeolite layer has a thickness and pore diameter so as to permit water desalination by the zeolite membrane through reverse osmosis at a pressure in a range from about atmospheric pressure to about 5000 kPa. 
     
     
         18 . A method as in  claim 1 , wherein the zeolite layer has a thickness and pore diameter so as to permit water desalination by the zeolite membrane through reverse osmosis at a pressure in a range from about 100 kPa to about 1000 kPa. 
     
     
         19 . A method as in  claim 1 , wherein the zeolite layer has a thickness and pore diameter so as to permit water desalination by the zeolite membrane through reverse osmosis during which water forced through the zeolite membrane has a flux greater than about 1 kgm −2 h −1 . 
     
     
         20 . A method as in  claim 1 , wherein the zeolite layer has a thickness and pore diameter so as to permit water desalination by the zeolite membrane through reverse osmosis during which water forced through the zeolite membrane has a flux greater than about 1.5 kgm −2 h −1 . 
     
     
         21 . A method as in  claim 1 , wherein the zeolite layer has a thickness and pore diameter so as to permit water desalination by the zeolite membrane through reverse osmosis during which water forced through the zeolite membrane has a concentration of dissolved ions is in a range between 1% and 8% by weight. 
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . A method as in  claim 1 , wherein the zeolite membrane has a pore diameter in a range from about 3 angstroms to about 8 angstroms, which allows water to flow through the zeolite membrane at a high flux rate while excluding dissolved aqueous ions from passing through the zeolite membrane. 
     
     
         25 . A method as in  claim 1 , wherein the zeolite membrane has a pore diameter in a range from about 4 angstroms to about 7 angstroms, which allows water to flow through the zeolite membrane at a high flux rate while excluding dissolved aqueous ions from passing through the zeolite membrane. 
     
     
         26 . A method as in  claim 1 , wherein the zeolite membrane has a pore diameter in a range from about 4.5 angstroms to about 6 angstroms, which allows water to flow through the zeolite membrane at a high flux rate while excluding dissolved aqueous ions from passing through the zeolite membrane. 
     
     
         27 . A method as in  claim 1 , wherein the thickness of the zeolite layer is in a range from about 15 microns to about 100 microns. 
     
     
         28 . A method as in  claim 1 , wherein the zeolite membrane is composed of the support material and the zeolite layer and has a thickness in a range of about 1 mm to about 20 mm. 
     
     
         29 . A method for making a zeolite membrane suitable for desalinating water using reverse osmosis comprising:
 providing a support material;   providing a plurality of zeolite seed particles for use in forming a zeolite layer on the support material that is suitable for use in desalinating water using reverse osmosis, the zeolite seed particles comprising a zeolite with a pore diameter in a range from about 3 angstroms to about 8 angstroms;   depositing the zeolite seed particles on the support material to form an intermediate supported zeolite in preparation for forming the zeolite layer; and   performing a secondary growth of the zeolite seed particles by combining the intermediate supported zeolite with a zeolite reaction mixture and growing the zeolite seed particles under conditions suitable for zeolite crystal growth so as to form the zeolite layer on the support material and thereby form a zeolite membrane comprised of the support material and the zeolite layer, the zeolite layer having a thickness greater than about 15 microns, the zeolite membrane having a thickness greater than about 1 mm and a pore diameter in a range from about 3 angstroms to about 8 angstroms, which allows water to flow through the zeolite membrane at a high flux rate while excluding dissolved aqueous ions from passing through the zeolite membrane.   
     
     
         30 . A method for making a zeolite membrane suitable for desalinating water using reverse osmosis comprising:
 providing a support material;   providing a plurality of zeolite seed particles for use in forming a zeolite layer on the support material that is suitable for use in desalinating water using reverse osmosis, the zeolite seed particles comprising a zeolite with a pore diameter in a range from about 3 angstroms to about 8 angstroms;   depositing the zeolite seed particles on the support material to form an intermediate supported zeolite in preparation for forming the zeolite layer; and   performing a secondary growth of the zeolite seed particles by combining the intermediate supported zeolite with a zeolite reaction mixture and growing the zeolite seed particles at a temperature greater than about 130° C. and under conditions suitable for zeolite crystal growth and so as to form the zeolite layer on the support material and thereby form a zeolite membrane comprised of the support material and the zeolite layer, the zeolite membrane having a thickness and a pore diameter in order to provide flux and ion rejection rates suitable for water desalination.